Final answer:
The subject-verb agreement in the given sentence is incorrect; the verb should match the part of the compound subject closest to it, which may be 'places' or 'place' depending on whether 'neighbor' is singular or plural.'Someone either my neighbors, or a stranger, place my garbage can back where it belongs' if 'neighbors' is plural.
Step-by-step explanation:
The sentence 'Someone either my neighbor, or a stranger places my garbage can back where it belongs' has an incorrect subject-verb agreement. In sentences where the compound subject is joined by 'or' or 'nor', the verb should agree with the part of the subject that is closest to it.
Therefore, the correct sentence would be: 'Someone either my neighbor, or a stranger, places my garbage can back where it belongs' if 'neighbor' is singular, or 'Someone either my neighbors, or a stranger, place my garbage can back where it belongs' if 'neighbors' is plural.
The correct subject-verb agreement depends on the proximity of the subject components to the verb in the sentence structure. This rule applies in cases involving indefinite pronouns and compound subjects.